Early Olfactory Experience and Later Social Behavior in the Rat: Preference, Sexual Responsiveness, and Care of Young

We recently showed that odorizing mother's nipples from birth to weaning attenuated adult conditioned odor aversion (COA). The present study evaluated whether shorter durations of preweaning olfactory experiences could induce similar long-term effects. We first showed that late preweaning odorization (PN13-PN25) impaired adult COA similarly to odorization from birth to weaning (PN0-PN25) whereas early odorization (PN0-PN12) had no effect on adult COA. As early odorization was followed by an odorless suckling period, we evaluated whether this odorless suckling could have interfered with early associative learning. We therefore weaned the animals either immediately after early odorization or 7 days later. Early odorization (PN0-PN18) followed by late odorless suckling (PN19-PN25) had no effect on adult COA. However, pups with early odorization (PN0-PN18) but without late odorless suckling (weaned at PN18) showed attenuated COA. These results support the hypothesis that interference between early and late preweaning experiences with the mother determines the long-term impact on adult COA.

Section: Discussionmentioning

confidence: 96%

Section: Introductionmentioning

confidence: 94%

Long‐term effects of infant learning on adult conditioned odor aversion are determined by the last preweaning experience

Sevelinges¹,

Mouly

Lévy³

2009

“…Studies with rodents suggest that early olfactory experiences also influence such subsequent behaviors as sexual responsiveness and social preferences (Carter & Marr, 1970;Mainardi, Marsan, & Pasquali, 1965;Marr & Gardner, 1965;Marr & Lilliston. 1970).…”

Section: Discussionmentioning

confidence: 97%

Olfactory discrimination of squirrel monkey mothers by their infants

Kaplan

Cubicciotti

Redican

1977

Infant squirrel monkeys, 8 to 24 weeks of age, were tested for their ability to discriminate their own mother from another lactating mother by means of olfactory cues, visual cues, or a combination of both. Discrimination by olfactory cues was unequivocal. Addition of static visual cues did not enhance discrimination, and infants showed little evidence of discriminating the mother by means of static visual cues alone. These results suggest that olfaction may be a more significant factor in primate early attachment than has generally been assumed.

“…These data strongly suggest that the artificial odorization of the early olfactory environment both disrupts and alters the normal olfactory environment, and as a result, disrupts the full and normal expression of maternal behavior much as it has been shown to disrupt male sexual behavior (Marr & Gardner, 1965). The fact that exposure to the odor out of the context of the nest or the mother did not delay the onset of maternal behavior suggests that the delaying effect is not due to exposure to a novel odorant, per se; however, our control condition may not be a good test of this hypothesis, as animals were not required to sniff a lemon-scented object, nor were they exposed to the lemon odor continuously as were the mother-reared animals with lemon-scented mothers.…”

Section: Discussionmentioning

confidence: 92%

Effects of preweaning exposure to novel maternal odors on maternal responsiveness and selectivity in adulthood

Shah

Oxley

Lovic

et al. 2002

We examined the effects of odor exposure in the nest on the offspring's subsequent adult responsivity to pups scented with the same odor or a different odor. It was hypothesized that animals receiving exposure to the odor in the nest would be more maternally responsive to pups scented with the (same) exposed odor than to unscented (water-scented) pups. In the first part of the study (Part A), Sprague-Dawley female rat pups (days 1-18 of age) either received exposure to an artificial lemon odor or to the natural (water) odor in the nest. In the second part of the study (Part B), rat pups were exposed daily to lemon or neutral odorants in an incubator at a distance from the mother and the nest. On day 21, animals received odor preference tests for lemon versus neutral pine bedding. On day 60, animals were mated and their pups were removed at 15-min intervals at the time of parturition. Animals were then tested for maternal behavior to foster pups on day 1 or 7 after parturition. Foster pups were scented either with the lemon odor or with water (unscented). Early exposure to lemon in the nest context enhanced animals' attraction to the lemon odor in juvenile tests. In adult maternal tests, exposure to odor on the mother and in the nest had two effects. It increased the latency for animals to express maternal behavior; however, once mothers expressed maternal behavior, they spent more time licking and crouching over pups scented with the same odorant to which they had been exposed earlier on their own mothers. Simple exposure to the lemon odorant out of context of the nest had no effect on adult maternal latencies or behavior.